(Press-News.org) The PSA screening test for prostate cancer is not perfect. It can indicate cancer when none is present and miss life-threatening tumors. But a new study suggests the test is more reliable in men taking dutasteride (Avodart®), a drug widely prescribed to shrink an enlarged prostate gland.
Dutasteride lowers PSA levels by about half within six months. But the researchers found that even a slight rise in PSA levels among men taking the drug was a stronger indicator of prostate cancer, particularly aggressive tumors that require early diagnosis and treatment, than rising PSA levels in men who took a placebo.
"Dutasteride stabilizes the amount of PSA that comes from enlarged prostates and low-grade cancers," says lead author Gerald Andriole, MD, the Robert Killian Royce, MD, Distinguished Professor and chief of urologic surgery at Washington University School of Medicine in St. Louis. "This enhances a rising PSA's ability to detect high-grade cancers that require early diagnosis and treatment, while reducing the discovery of tumors that are unlikely to cause harm if left untreated."
The study is now available online and will be published in January in the Journal of Urology.
The PSA test measures the amount of prostate-specific antigen in the blood. The larger a man's prostate, the more PSA he produces. Elevated levels can point to cancer. But PSA often rises naturally as men age, mainly due to benign prostatic hyperplasia (BPH), a progressive enlargement of the prostate. This leads to many false positive PSA tests for cancer. Indeed, biopsies only find cancer in about one in four men with an elevated PSA.
In the new study, the researchers looked more closely at data from a four-year trial that evaluated whether dutasteride could reduce the risk of detecting prostate cancer in men with an increased risk of the disease. The study involved 8,231 men ages 50-75 who were randomly assigned to receive a placebo or a daily 0.5 mg dose of dutasteride. The men had elevated PSA levels (2.5 ng/ml-10 ng/ml) but no evidence of cancer on biopsies performed within six months of enrolling in the trial.
Results published earlier this year in the New England Journal of Medicine showed that dutasteride reduced the risk of a prostate cancer diagnosis by 23 percent. Dutasteride appears to keep tumors small or shrink them to the point that they are less likely to be detected by a biopsy, says Andriole, who led the steering committee that oversaw the earlier trial.
In the current analysis, the researchers looked at the performance of PSA as a marker for prostate cancer, particularly for aggressive cancer. Among men taking dutasteride, the investigators found that any subsequent rise in PSA levels over the course of the study was more likely to be linked to aggressive, high-grade tumors (Gleason score 7-10), compared to rising PSA levels in men on a placebo.
The Gleason scoring system measures tumor aggressiveness based on biopsy results and can range from 2-10, with 10 being the most aggressive.
"If a man is taking dutastride and his PSA level starts to rise, he has a higher chance of having an aggressive cancer," Andriole says. "This makes PSA a more effective screening tool for prostate cancer but even more importantly for aggressive cancer."
Over four years, PSA levels increased in 72 percent of men taking a placebo and only 29 percent of men taking dutasteride, the data show. However, there was no significant difference in high-grade tumors between the two groups.
Men taking dutasteride were almost twice as likely to have aggressive prostate cancer if their PSA levels rose, compared to men whose PSA levels went up while taking a placebo. In men with any increase in PSA, aggressive, high-grade tumors were diagnosed in 13.2 percent of those on dutasteride and 7.7 percent of those taking a placebo.
Even a slight rise in PSA levels was a more accurate predictor of aggressive tumors. Among men whose PSA levels increased one point or less, 10.3 percent of those taking dutasteride had aggressive cancer, compared with 5.4 percent taking a placebo.
That trend also held for larger increases in PSA levels. Among men whose PSA levels rose two points or more, nearly 20.9 percent of those taking dutasteride had aggressive cancer, compared with 9.8 percent taking a placebo.
In contrast, PSA levels tended to decrease or remain stable in men taking dutasteride who either had low-grade tumors or no cancer at all.
The study's authors do not suggest that men take dutasteride just to get a more accurate readout of PSA levels attributable to cancer. "However, men who are taking dutasteride can be confident that the drug does not weaken the ability of PSA to find cancer if it develops," Andriole says. "Rather, the drug enhances the ability to find cancer if PSA levels are rising."
###
Editor's note: Dr. Andriole is a consultant for GlaxoSmithKline, the manufacturer of Avodart® and the study's sponsor.
Andriole GL, Bostwick D, Brawley OW, Gomella L, Marberger M, Montorsi F, Pettaway, Tammela TLJ, Teloken C, Tindall D, Freedland SJ, Somerville MC, Wilson TH, Fowler I, Castro R, Rittmaster RS. The effect of dutastride on the usefulness of prostate specific antigen for the diagnosis of high grade and clinical relevant prostate cancer in men with a previous negative biopsy: Results from the REDUCE study. Journal of Urology, January 2011.
Washington University School of Medicine's 2,100 employed and volunteer faculty physicians also are the medical staff of Barnes-Jewish and St. Louis Children's hospitals. The School of Medicine is one of the leading medical research, teaching and patient care institutions in the nation, currently ranked fourth in the nation by U.S. News & World Report. Through its affiliations with Barnes-Jewish and St. Louis Children's hospitals, the School of Medicine is linked to BJC HealthCare.
END
(Boston) - Current diagnostic procedures for posttraumatic stress disorder (PTSD) fail to adequately reflect research into the broad nature of a traumatic event, according to a study that will appear in the January print issue of Psychological Bulletin.
The relevancy of an individual's subjective experience in determining what constitutes a traumatic event has been a source of debate among PTSD specialists for years. The study concludes that both objective and subjective factors are relevant and that current PTSD criteria are missing several reactions that many trauma ...
A new genetic biomarker that indicates an increased risk for developing breast cancer can be found in an individual's "junk" (non-coding) DNA, according to a new study featuring work from researchers at the Virginia Bioinformatics Institute (VBI) at Virginia Tech and their colleagues.
The multidisciplinary team found that longer DNA sequences of a repetitive microsatellite were much more likely to be present in breast cancer patients than healthy volunteers. The particular repeated DNA sequence in the control (promoter) region of the estrogen-related receptor gamma (ERR-γ) ...
New Rochelle, NY, December 16, 2010 – Former tennis champion Martina Navratilova was hospitalized for pulmonary edema—fluid build-up in the lungs—while climbing Mount Kilimanjaro, drawing attention to the high risk of acute mountain sickness (AMS) and high altitude pulmonary edema among climbers of high peaks. A timely study in a recent issue of High Altitude Medicine & Biology, a peer-reviewed journal published by Mary Ann Liebert, Inc. (www.liebertpub.com), warned of the risks and serious medical outcomes associated with climbing Kilimanjaro and demonstrated that prior ...
Long before Facebook introduced its hot new Social Graph app, researchers in the ADVANCE project at NJIT were pioneering the use of social network mapping to help women scientists and engineers supercharge their careers.
"Universities are more than buildings and balance sheets. They're webs of human interaction," said Nancy Steffen-Fluhr, director of NJIT's Murray Center for Women in Technology and the ADVANCE project leader. "The complex structure of those webs is largely invisible to the people embedded in them, however -- especially women scientists and engineers. ...
Without Social Security, research indicates that about half of women age 65 and older would be living in poverty. With the program in place, the poverty rate for women falls to 12 percent. These facts — paired with recommended future courses of action — are presented in the latest installment of the Public Policy & Aging Research Brief series from the National Academy on an Aging Society, the public policy branch of The Gerontological Society of America (GSA).
The new publication, "For Millions of Older Women, Social Security Is a Lifeline," was funded by grant support ...
UCSF researchers have shown for the first time that the human fetal immune system arises from an entirely different source than the adult immune system, and is more likely to tolerate than fight foreign substances in its environment.
The finding could lead to a better understanding of how newborns respond to both infections and vaccines, and may explain such conundrums as why many infants of HIV-positive mothers are not infected with the disease before birth, the researchers said.
It also could help scientists better understand how childhood allergies develop, as well ...
ANN ARBOR, Mich.---There's a whale of a new display at the University of Michigan Exhibit Museum of Natural History, a leviathan that represents a scientific saga of equally grand proportions.
A complete, 50-foot-long skeleton of the extinct whale Basilosaurus isis, which lived 37 million years ago, now is suspended from the ceiling of the museum's second floor gallery and will reign over an updated whale evolution exhibit scheduled to open in April 2011.
"It's a spectacular fossil," said Exhibit Museum director Amy Harris. "Basilosaurus looks ferocious with its big ...
Xlibris Publishing, a leader in the self publishing industry, recently announced the latest addition to their self publishing services, the Xlibris Audio Book Publishing Packages. Whatever type of published book the author has, he can now share it to the world as a first-class audio book.
Available in five different services, Touchstone, Compact, Amplified, Storytale and Paramount, the Xlibris Audio Publishing Service produces a digital version of an audio book for the author while the high end packages involve digital availability of the author's books through Overdrive ...
New independent research carried out by Local Traders in the UK has shown that more than 60% of people use online services to find tradespeople than traditional directories, and as many as 80% won't use a paper based phone directory to aide their search.
Results from research conducted at the start of December has shown that the majority of people are turning to the internet and online services when they need to find tradespeople to carry out work on their homes.
2000 people living in the UK were surveyed in the recently conducted independent research, carried out ...
Tarpaflex, an internet based tarps ( http://www.tarpaflex.com ) company, specializes in providing seven popular qualities of tarps online and has been successfully established as a widely known Tarpaulin company for 25 long years now. The latest client for Tarpaflex being the 2012 Olympic stadium in London for their exquisite blue tarps, Tarpaflex has come a long way in spreading its brand name with top notch clients and pride themselves in being one of the rare family owned and operated company as worthy competitors to their larger business contemporaries.
Tarpaflex ...